Manchester City boss Roberto Mancini has been critical of their transfer work.
Among several targets they missed out on included Manchester United striker Robin van Persie.
Mancini told The Guardian: "It's important to realise we have made some mistakes.
"I have made some mistakes and the players have made some mistakes.
"But the first reason is because we didn't do what we should have done in the summer transfer market - we worked really badly in the market."